This application claims priority from U.S. Provisional Application 61/022,379 filed Jan. 21, 2008, the entirety of which is incorporated herein by reference.
In response to environmental concerns cleaning compositions containing chlorofluorocarbons (CFC's), which have been widely available for use in cleaning electronic devices, are being phased out. As a result, there is significant need and interest in developing more environmentally stable cleaning compositions that are still effective for use in and around electronics, to clean and remove dust, solder, flux, oils and other similar contaminants that, for example, often attend the manufacture of circuit boards.
In addition to providing environmentally sound, but effective cleaning compositions, it is also important that the cleaner not cause damage to the electronics, or to the other types of substrates commonly found in electronic devices. It is particularly a challenge, but extremely desirable, to provide an effective electronics cleaner that will not harm plastic components and substrates that are widely used in the body of the device or as internal structural elements. Given the wide variety of plastics that can be used in electronic devices, such as polycarbonate (PC), acrylonitrile butadiene styrene (ABS) or PC-ABS blends, it is reasonable that a consumer is not knowledgeable about what specific type(s) of plastic are contained in a particular device. This can make proper selection and use of a cleaner more difficult, as many may be safe for some types of plastic but not others.
The effect of many existing electronics cleaners on plastic can range from aesthetic harm, such as discoloration or a change in gloss, to structural harm, such as melting or crazing. Even if the effect of using these cleaning solutions on plastic parts is a purely aesthetic, it is an extremely undesirable side effect. Notwithstanding, it is a side effect that is difficult to avoid or predict in using existing products. Overspray is common during application and plastic is often so intertwined with the electronics to be cleaned as to make it impractical to apply a cleaner to one but not the other.
There is a need, therefore, for a cleaning composition having sufficient character and robustness to clean contaminated substrates of flux, solder, dust, fingerprints, and the like, and particularly substrates comprising electronics, but which is also safe for plastic components associated with or comprising part of the substrate. The cleaning compositions should sufficiently evaporate so as to leave no or substantially no residue, while being substantially nonflammable, relative non-conductive and having low toxicity. The present invention provides cleaning compositions that addresses this need.